How can a single magma generate several different igneous rocks?

Question

I'm taking an online class and cannot find an explanation in my materials. Help? Anyone?

Answer 1

The process is called magmatic or igneous differentiation:  As the magma cools, certain minerals will crystallise out first as they will have a higher melting point:  If they are removed from the parent magma by setttling, for example, then the composition of the magma will change, and new minerals will begin to crystallise.  The process can produce some very different igneous rocks from one magma.  The sites below give more detail.

Answer 2

differentiated cooling.  different areas of the same magma cool at different rates with different impurities in it.